I think I might. I excelled in school and yet my math grades were always around a C. I have a hard time keeping numbers in my head, they just disappear unless i focus really really hard to keep them there. I can remember many frustrated tears shed trying to do math homework, or being the last one still working on the math test. And yeah basically I need a calculator unless I really put a lot of effort to keep the numbers in my head, but at that point it feels like you're really straining a muscle so to speak. When I'm knitting, I sometimes have to count my stitches over and over because I forgot the number halfway through counting.
It's odd because at the same time, I'm really good at logic. I got a degree in computer science (but ended up being too autistic to get a job). I always got great grades for my programming work. I can remember taking a physics course and most of the time the math was just rearranging equations, where you're just dealing with the logic of switching the symbols around like m, t, d, etc, and plugging the numbers into the calculator. I was great at that, and even enjoyed it sometimes. But the damn numbers, man. If our physics teacher didn't let us use calculators I would have failed. So in my brain at least, it seems that arithmetic and logic are two separate things.